Boat Electrical: How to Wire a Bilge Pump 

For single handed sailors a momentary switch isn’t very helpful. Instead to control and protect my two bilge pumps, I use a Blue Sea 1522. It has a restricted off circuit breaker with manual override switch and two LED’s for each pump. One LED indicates power available at the float switch, the second LED indicates the pump is running by float switch activation or from the manual override switch. Great video, thanks for taking the time to put it together.

For someone who’s trying to get prepared before buying a boat in a few years, these videos are perfect. Thank you so much!

Good explanation, particularly like the led add on....,thanks

Nice! When 'simple' is explained simply; 'complicated' becomes easier to understand.

I continue to enjoy your series immensely, especially your teaching style. Suggest that maybe you could add a simple schematic drawing of the circuit, just to familiarize us to the symbols we would encounter along the way. Great job. I am looking forward to the next one!

Guys keep them coming. I don't know what I don't know 😁

Loving this series. Sometimes it's hard to see what's being connected where, but your explanations are really great. Thank you!

Thanks. Needed a refresher before diving into my bilge.

That was awesome Clark. Thank you everyone has a little bilge pump so this was very helpful. I appreciate the pictorial so we could see the hot and ground connections through the entire circuit. Well done,

You're going through a nicely thought out sequence of lessons. I'm looking forward to those to come. Good work, and thanks very much!

I'm really enjoying this series! I have a very basic understanding and can get by with small repairs and installs but you have broadened my horizons! I appreciate that you're breaking it down to it's simplest form as well. Thanks for taking the time and effort to make these videos.

Again, great video and great lab.

Great practical stuff. Thank you

Thanks Clark. I can't help but think about how much time you spent setting this up for us. Very much appreciated. Great presentation!

I love how you reply to everyone ! Great video, well spoken.

IT’s always fun to watch & learn, thank you

Caught back up! Another phenomenal explanation keeping things clear and concise. My poor overworked brain thanks you! This series couldn't come at a more perfect time as I'm designing and getting ready to install a complete solar system on my boat within the next two months. I'm actually understanding everything you are teaching so far, Thank you!

Another Master Class! Thanks! I can now see how and why the switchboard (behind them, at least) are SO packed with all kinds of wires and such additional (and necessary) elements. You give the appropriate name to each part, with the facts of use, to back each part up. Usually, when watching other channels do some electrical work, or refits, or upgrades, etc, they fail to explain these steps. It generally just goes along the lines of "we connected the wires to the panel" and the perceived "wire mayhem" that ensues is maddening! Thanks again, professor!! 😅

Thanks Clark, very interesting and useful. 🙂

Great explanation love your series

Nice and clearly explained. Thank you.

Many thanks for posting, just about to install a new pump 🙏⛵️

Awesome Clark. I understood how this circuit worked but didn't think about a light. Now I can stop worrying and always checking to make sure it's working. Thanks for the peace of mind. And the physics that you throw in is always interesting.

Great video!! Perfectly explained, simple and great visuals!! Even I understood it! 😂👍🏻

Great Video. I am learning so much! Thank you

Clear & concise. Thanks!

Excellent Clark, you are a Master Instructor

Great explanation---thanks!

Just found your channel and its great! I see a ton of videos that are going to help me tremendously once spring arrives and I can get to repairs on my new fixer upper.

Thank you. Thank you. Thank you. I teach a lot of classes on very complicated topics (HVAC design, airflow, thermodynamics, building science, energy efficiency, energy codes, etc.) Not only did I learn about the topic at hand but what a total noob feels like when they are trying to learn something new and clearly the instructor is years and years ahead of them. You did a great job and I will be altering my training approach accordingly.

Thank you so much for the clarification. Super.

Excellent presentation- very well explained !

Thank you. VERY good video.

Clearly explained. Well done.

Thank you! I enjoyed your video.

Fantastically clear, concise and instructive. Thank you!!

Thanks mate, great stuff

Awesome great work threw really like the led I don’t have that thanks👍👍

Very engaging!

Excellent video

Nice vid Clark!

Great video!

Great class.....love it. Maybe add GPH.....head pressure.....check valve...hose diameter and flow rates with bends and length......enjoy the heck out of channel.

Great video.

Great Clark :-)

Draw a Y. Place V in top of Y. Place R in bottom left. Place I in bottom right. Then draw a V as an extension to upper right arm of Y. Place a P (power) within the drawn V. This gives P over VxI. Much easier to draw than describe. Try it I think you'll like it. PS: excellent tutorials.

good stuff! thanks

very helpful

cool video, would love to see more of that!

Clark, no need to worry about the fuse or the wire on the LED circuit. An LED draws typically between 10-20 mA, that wire will be perfectly fine! :)

Great job Clark! It still amazes me how many boats barely even have ONE working bilge pump and many times its rigged up simply to a manual switch...that works sometimes..lol.

Clarke, love your technical series! Can't wait until you get to multi-source charging systems, trouble shooting and wire tracing. But I understand, foundations before towers.

Thanks Clark! This was very interesting! Off to retire my bilge pumps - because after watching this, they aren’t right!

Now I want to play D&D! Great advice.

Welcome back,always enjoy your channel.In regard to Bilge pump install i am not fond of the controls, as i feel the wire size at the control,i.e. from battery to control and control to float switch is too small, especially with a long run, so i use a solenoid, that way there is no voltage drop.

It’s late where I am Clark but since I’ve had a couple of boats sink I thought I’d better watch this! Lol

Since you've dropped that bomb of electron flow direction on their heads, go for broke and hit 'em with Hole Theory!😁 Great video on a simple but highly necessary item.

I like what you did, and it's also nice to start out with a simple circuit with 12 volt lights, series / parallel and talk about voltage drop and current. You may be planning on that in the future as they can get complicated real fast with resistors and math as I'm sure you know. I also think it's a great idea to start out with simple schematic drawing of the circuit, which would help to familiarize viewers with the symbols they will see in real life. I'm trying to say its good to see actual components, but seeing the circuit in a schematic or wiring diagram makes following the components in a circuit that much easier... It give us a road map so we don't get lost, just like driving a car through a city or sailing a boat with charts. Cheers....

I was wondering if you were going to explain that electrons actually flow from negative to positive, and you did. I like the trick with lighting the LED from the other end. Keep the good stuff coming.

Excel video, as usual. You might emphasize that in any circuit running a motor, that machine can get physically jammed by debris or an adjacent part failing. Pay special attention to fusing on motor circuits!

Nice job Clark. Say hi to Emily.

CLARK... GREAT INFO AND GREAT PRESENTATION... I have a more advanced bilge wiring issue to run past you.... specifically: I am in the process of replacing my Rule Automatic pump model ( 27SA) . It has three wires... a Black ground wire......a Brown automatic wire.( which is always live with 12 volts) and a Brown and White manual wire which only has voltage when the manual test switch is thrown. . The Brown automatic wire sends a short pulse every 2.5 min down to the pump to sense for water. If water is detected it stays on until the water level is reduced...... So before installing it I used a multi meter to test that I have voltage at the brown wire .For some reason the automatic function does not work even though I have voltage.... I tested the pump on a 12 volt car battery charger and it works fine... so the pump is ok. So im wondering what is stopping the auto function from working..... my only guess so far is maybe the wire is not providing enough amperage due to corrosion.... Any suggestions would be appreciated. Ps... I also did a work around where I ran a hot wire from another part of the boat to the pump and it worked fine... so the pump is good but I cant figure out why the existing hot wire could have voltage but will not activate the atutomatic part of the pump... hope u can help Please drop me a line at captainlar7@gmail.com ..... thanks Larry Boyd... I can give you my phone number if you drop me an e mail...

Doing good Work to make marinas a safer place for all :-) I see so many fuses at the appliance side with an unprotected wire running all the length of the boat.

Good example and the most serviced circuit on a boat. Breaker panel manufacturers don't protect their led microwires, the led is considered current limiting and in housing. I would just keep the same size wire as protected circuit till at indicator led in a safe box. Can also install a breaker open and power on in addition to the closed circuit.

Single POLE. Or Double POLE Fuses are there to protect the wiring, not the device - it's worthwhile thinking in terms of that if you're doing any wiring. (momentary ON switches are designated (ON). Off is shown OFF. Always on shown as ON) The are two types of ON & (ON) switches, ON-OFF-(ON), & OFF-ON-(ON) with the latter used in things like dual function run/kill switches and key switches. There is a sensational chart showing you the amperage over a distance chart. The longer the RETURN distance*, the thicker the wiring needs to be to carry that current (amperage). Otherwise the wire can still overheat and cause a fire. *the RETURN distance is the entire length of the wire from the battery, through the switch, and back the battery..... not so hard to imagine when your wiring a fibreglass hull but often overlooked when you are using a chassis in a car or a metal hull as your earth/return/negative.

I've seen others put a timer delay relay in the bilge circuit so if the float switch bounces up when a wave comes or water in the bilge splashes the float switch it doesn't turn on the pump for a few seconds. The circuit has to be active for 10 seconds before the relay kicks in and actives the pump. This can also be used to delay the "off" of the circuit to get the bilge more water free than a float switch could make it.

Great video! Really helpful for a rookie! To that end, if possible could you mention the wire sizes in future videos. It would make it easier to know what the needs/differences are in each circuit.

YT recommended this video to me today. How did they know we are working on the bilge pump tomorrow? Spooky :)

Another great video - thank you! What do you think about the strategy of having the float switch also wired directly to the battery (via a fuse) so it'll work if the panel switch is accidentally left off, or there's a defect in the switch? Mine's wired like you described (without the handy momentary option), but I've heard the other theory mentioned.

Clarke....great video and I thank you. Can you explain how I turn off house power when leaving yacht but keep bilge auto mode on. Thanks !

Oooh! Hex Map! Hex map = Gamer!

Excellent video, thank you! Finding your videos very helpful. Question: Where you’ve placed the circuit breaker in this video, could an inline fuse holder be used safely there instead? Any advantage/disadvantages to either? Thanks again!

Okay, call me silly safety guy but I'm still wiring the indicator light with heavy enough wire to match the rest of the circuit & breaker or I'm putting a fuse in it (where it's easily accessible near the panel / switch / light). Besides, good excuse to toss up another comment for you. Safe travels in Indy and have a blast you two!

Wow what a great series you have going. You wouldn't happen to have any interest in designing a complete electrical system?

That's why you disconnect negative first.

Clark another great video, very educational. I had a situation the other day on a boat where the pump started working in reverse. No wires were changed and to my knowledge nothing (maintenance) was done to the boat. I discovered it by accident. The pump was running due to the float switch being triggered, but no water was being pumped out of the bilge. I thought the impeller was broken so I opened the cover flipped the switch and saw that the impeller was turning in the wrong direction. I flipped the pump wired and it worked correctly then. What could have made the reversal?

I love this set up. I've been looking all over for the circuit switch. Can you share the link. I only found momentary off momentary

Check out Water Witch float switch. No moving parts. Im done with that style float switch.

👍!!!

Great job. BTW- single POLE, not single-pull.

Great video Clark, I needed to draw my own schematic to see how the LED was wired, and how it works. Do you have wiring schematics for Temptress?

Hi Clark, This is a great series and much appreciated! I have a question about the position of the fuse. It is positioned on the positive side of the circuit however you said that current runs from the negative side of the battery through the circuit to the positive side of the battery. If this is the current flow then why is the fuse not on the negative side to protect the flow?

Nice to hear someone broach the pos-neg flow issue. Hope you didn't open a can of worms. Any tig welder would understand your thinking. Electrode pos vs. neg. Heat in the work or in the tungsten....balance is in there on the AC welding but similar Theory. Personally, while it's easier to understand neg to pos flow, isn't it more correct to say a circuit is just instantaneously charged?

Great video series I know the bare basics about electricity so this series has ben extremely helpful. I have what may be a dumb question but how do I go about tracing the wiring back to the electrical panel? For example if I wanted to replace the wiring to my bilge pump.

Thank you for the great content.. I really like your ac concept. QUESTION: I'm wiring a 12 volt horn that is 6 amps. I have 5 amp fuses and 7.5 amp fuses. What would you recommend? I leaning towards the 5 amp... Thanks, Jon

+ adds electrons to the battery - takes electrons from the battery

If electrons actually flow from the negative terminal to the positive terminal , does that mean the safest place for the circuit breaker is beside the negative terminal and not the positive? Your videos are awesome and you are an excellent teacher.

If like you said the electricity travels from negative to positive, why do you put the fuse by the positive terminal? Wouldn't that just protect the short wire from fuse to positive terminal? I apologise if I misunderstood something. Thanks for putting these videos out.

Wow, great videos ! We are just new to 12v and I can't seem to make seem to sense of the logic of protecting a wire with a fuse very near to the energy source... when in fact the energy is running through the circuit from the opposite direction (the black) so the fuse is at the end of the run of wire. You showed us how fast the wire burned in the last video. Are you telling us that if you had put a fuse into that circuit (the one that you burned the wire), that the fuse would have really burned out before that wire burned (even though it was down river)?

Would wiring the LED in series between the pump and the battery achieve the same thing, as in it would be powered when and only when the pump is operating?

If the float is activated and you hit the momentary switch will it backfeed and blow the circuit or fuze?😊

One question if you found it interesting. Why to put the fuse on the positive side of the batt if the current is flowing from the negative side?

That would be a single POLE single throw switch. Excellent explanation of a simple DC circuit.

What are your thoughts on similar bilge pumps, but that are automatic with an internal float switch? Seems like they would take up less space and less likely to have a stray wire hold the float switch down.

Clearly illustrated.

Clark, back when you did the episode on your Lund Dinghy, you mentioned that you had built your aluminum dinghies at one time. Do you have any plans or photos of how you were building them. Thank you for your time and your videos

My bilge is not very big. Is there any bilgepumps on the market with an internal floatswitch. If yes - do you recommend a pump like that?

A log meter might be interesting to include to track the time or just instances of the pump running in a given period of time. But you might drive yourself crazy given all the variables.

Can I use adaptor for that intead of battery? And how much amp do i need it to work, seems like 12v 2amps isn't working,do i need Higher amps?

wouldn't you want this wired straight to the battery for when it is sitting in the water unattended (like at a marina)?